With the growing need of processing image information with the computer equipments, the image scanning device is gaining in popularity.
To scan an image, a light is first directed onto an image information to be scanned. The reflect light from the image information is then arranged to pass a light filter apparatus, which typically is rotating in a high speed, for chromatic filtration of the reflect light. One single chromatic primary color, e.g. Red, Green, or Blue, passing through the light filter apparatus at any moment is then fed to a charged coupled device (CCD) through a lens. Many different conventional types of light filter apparatus which are discussed and summarized in the issued Patent (Publication No. 149980) of Taiwan, Republic of China, the entire contents of which are herein expressly incorporated by reference.
However, not to mention other shortcomings, for the manufacture of the light filter apparatus protected by the mentioned R.O.C. patent, a rather complex injection die comprising at least six slide blocks is required when the apparatus is to be used in a color scanning device.